Improvement in electro-magnetic annunciators



A. s. WETMORE. ELECTRO-MAGNETICJANNUNCIATOR.

No. 178,216 Patented May 30,1876.

N.PEYERS. FNOTO-LITHOGRAPHER, WASHINGTON. D c.

UNITED STATES PATENT QFFIC'EL ALBERT s. WETMoRE, oFoLEvELANn, OHIO,ASSIGNOR OF oNE-HALEHIs RIGHT To EDWARD MILL, OF SAME PLACE.

IMPROVEMENT IN ELECTRO-MAGINETIC ANNU'NCIATORS.

Specification forming part of Letters Patent No. 178,21 6, dated May 30,1876; application filed October 29, 1875.

To all whom it may concern:

of Ohio, have invented an Electric Annunciator, of which the followingis a specification:

This invention relates to a new construction of electromagneticannunciators and consists in the combination, with an electro-inagnet,of a thin, magnetized steel armature, poised or balanced in an openingmade in a plate covering the front ends of the magnet, said plate alsoserving to insulate the armature from the magnet. The armature has arear projecting arm, which serves as a counter-balance to hold it upwhen disengaged, and bymeans of which it is also disengaged from themagnet, in connection with a suitable mechanical appliance for thatpurpose. The said armature has upon its outer face a number, which isbrought into view when drawn down by the electromagnet.

To enable others to fully understand my invention, I proceed to describethe same in detail with the aid of the accompanying drawing, in which-Figure 1 is a front view. Fig. 2 is a vertical section in line m w ofFig. 1. Fig. 3 is a detached View of the armature.

A is an electro-magnet, incased in a suitable box, B. To the front ofsaid box Ifix a metal plate, 0, next to the ends of the cores of themagnet A. The front side of said plate 0 may be coated with silver orcovered with paper. This plateinsulates the armature from the magnet. Dis a thin plate of magnetized steel, which serves both as the armatureand the number-plate. It has anarm, '11, which reaches inward, and.serves as a counterbalance to hold the armature up when disengaged fromthe magnet. The said armature is poised in a triangular opening, e, madein the plate 0, it having notches in the edge of the arm at its junctionwith the plate, so that it cannot slip out, and it is very easily tiltedby the attractive force of the magnet. F is a frame supported in springsff, and is situated just behind the plate G, and has a knob ,outside thecase. This frame is employed for disengaging the arm-ature from themagnet.

The operation of this arrangement is as follows: On closing the electriccircuit the armature D is attracted, and quickly turns down by theattractive force of the electro-magnet, bringing the number into View,as seen in Fig. 1, and it, being a permanentmagnet, will remain in thatposition after the electrical circuit has been broken, and it alsoadheres with considerable tenacity, so it is not liable to' be jarred orshaken off. When it is desired, however, to release it, the frame isdrawn down by the knob, which throws itinto the position seen in Fig. 2,and the arm d, over-balancing it, holds it up until the circuit is againclosed. I Having described my invention, I claim-- 1. The plate 0,placed in front of the magnets A as an insulating medium, through whichthe armature D is actuated, substantially as specified.

2. The combination, with themagnet A and ALFRED ELWELL.

